Copper-nickel-tin alloy with manganese

ABSTRACT

A copper-nickel-tin alloy contains from about 1.9 wt % to about 21 wt % manganese.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent Application Ser. No. 62/134,731, filed on Mar. 18, 2015. The entirety of this application is hereby fully incorporated by reference herein.

BACKGROUND

The present disclosure relates to copper-nickel-tin-manganese alloys.

Copper alloys used in oil exploration and production must exhibit high impact toughness (e.g., at least 20 ft-lbs). In metallurgy, the term “toughness” refers to the ability of an alloy to absorb energy and plastically deform without fracturing. Therefore, toughness requires a balance of strength and ductility. Alloys may also be exposed to corrosive materials such as hydrogen sulfide (H₂S) and deleterious conditions such as high bearing wear and friction. Hydrogen sulfide is a colorless gas which exhibits a foul odor like that of rotten eggs. Hydrogen sulfide is heavier than air, extremely poisonous, flammable, and explosive in addition to being highly corrosive. Additionally, aircraft landing systems require high resistance to low velocity, high load sliding bearing forces during takeoffs and landings.

It would be desirable to develop new alloys with high impact toughness, corrosion resistance, and resistance to bearing wear and friction.

BRIEF DESCRIPTION

The present disclosure relates to copper-nickel-tin-manganese alloys. The alloys exhibit high impact toughness and good resistance to corrosion, wear, and friction, particularly enhanced by fabrication deformation (cold work).

Disclosed in embodiments is an alloy including copper; nickel; tin; and from about 1.9 to about 20 wt % manganese.

In some embodiments, the nickel is present in an amount of from about 5 to about 25 wt % and/or the tin is present in an amount of from about 5 to about 10 wt %.

The manganese may be present in an amount of from about 1.9 to about 10 wt %, including from about 1.9 to about 5 wt %, from about 1.9 to about 2 wt %, and from about 2.0 to about 10 wt %.

Disclosed in other embodiments is an article comprising a copper-nickel-tin-manganese alloy. The manganese is present in in the alloy in an amount of from about 1.9 to about 20 wt %.

The article may be selected from the group consisting of a bushing, an instrument housing, a connector, a centralizer, a fastener, a drill collar, a mold for plastic shapes, a welding arm, an electrode, and a certified ingot.

In some embodiments, the article is in the shape of a strip, a rod, a bar, a tube, or a plate.

The alloy may include from about 5 to about 25 wt % nickel and from about 5 to about 10 wt % tin.

Optionally, the article has at least one dimension in excess of about 5 inches.

The article may be an aircraft landing system or a component thereof.

Disclosed in further embodiments is a method for producing an article. The method includes providing a copper-nickel-tin alloy; and adding 0.2 to 20 wt % manganese to the copper-nickel-tin alloy based on the total weight of the article.

Optionally, the method further includes cold working the article.

In some embodiments, the nickel is present in an amount of from about 5 to about 25 wt % of the article and/or the tin is present in an amount of from about 5 to about 10 wt % of the article.

The manganese may be present in an amount of from about 0.2 to about 10 wt %, including from about 0.2 to about 5 wt %, from about 0.2 to about 2 wt %, and from about 0.2 to about 1.9 wt %.

These and other non-limiting characteristics of the disclosure are more particularly disclosed below.

BRIEF DESCRIPTION OF THE DRAWINGS

The following is a brief description of the drawings, which are presented for the purposes of illustrating the exemplary embodiments disclosed herein and not for the purposes of limiting the same.

FIG. 1 is a flow chart illustrating an exemplary method of the present disclosure.

DETAILED DESCRIPTION

A more complete understanding of the components, processes and apparatuses disclosed herein can be obtained by reference to the accompanying drawings. These figures are merely schematic representations based on convenience and the ease of demonstrating the present disclosure, and are, therefore, not intended to indicate relative size and dimensions of the devices or components thereof and/or to define or limit the scope of the exemplary embodiments.

Although specific terms are used in the following description for the sake of clarity, these terms are intended to refer only to the particular structure of the embodiments selected for illustration in the drawings, and are not intended to define or limit the scope of the disclosure. In the drawings and the following description below, it is to be understood that like numeric designations refer to components of like function.

The singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise.

Numerical values in the specification and claims of this application should be understood to include numerical values which are the same when reduced to the same number of significant figures and numerical values which differ from the stated value by less than the experimental error of conventional measurement technique of the type described in the present application to determine the value.

All ranges disclosed herein are inclusive of the recited endpoint and independently combinable (for example, the range of “from 2 grams to 10 grams” is inclusive of the endpoints, 2 grams and 10 grams, and all the intermediate values). The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value; they are sufficiently imprecise to include values approximating these ranges and/or values.

A value modified by a term or terms, such as “about” and “substantially,” may not be limited to the precise value specified. The approximating language may correspond to the precision of an instrument for measuring the value. The modifier “about” should also be considered as disclosing the range defined by the absolute values of the two endpoints. For example, the expression “from about 2 to about 4” also discloses the range “from 2 to 4.”

As used herein, the term “spinodal alloy” refers to an alloy whose chemical composition is such that it is capable of undergoing spinodal decomposition. The term “spinodal alloy” refers to alloy chemistry, not physical state. Therefore, a “spinodal alloy” may or may not have undergone spinodal decomposition and may or not be in the process of undergoing spinodal decomposition.

FIG. 1 illustrates an exemplary method 100 for producing an article. The method 100 includes melting a copper-nickel-tin alloy 110; adding 0.2 to 20 wt % manganese to the copper-nickel-tin alloy based on the total weight of the article 120; casting the alloy 125; optionally solution annealing 130; optionally cold working the article 140; and optionally heat treating the article 150.

The copper-nickel-tin alloy may be a spinodal alloy.

The preparation of a properly proportioned batch of copper, nickel, and tin is followed by melting 110 the combination. The melting 110 may be carried out in a gas-fired, electrical induction or arc furnace of a size matched to the desired solidified product configuration. Typically, the melting temperatures is at least about 2057° F. with a superheat dependent on the casting process and in the range of 150 to 400° F.

The addition of manganese 120 may be carried out by dissolving the manganese into the melt at a temperature of at least about 2100° F. and preferably in the range of from about 2200 to about 2350° F.

Next, the alloy is cast 125. Casting of the alloy may be performed following melt temperature stabilization with appropriate superheat into continuous cast billets or shapes. In addition, casting may also be performed to produce ingots, semi-finished parts, near-net parts, shot, pre-alloyed powder, or other discrete forms.

In some embodiments, some magnesium is added during the melting 110, adding 120, and/or solution annealing 130 in order to reduce the oxygen content of the alloy. Magnesium oxide is formed which can be removed from the alloy mass.

Strength may also be improved via work hardening (e.g., cold working 140) and/or a spinodal aging treatment. These features improve overall strength-ductility combinations while achieving improvements in other properties such as strength-impact toughness combinations, corrosion resistance, and bearing qualities.

Cold working is the strengthening of a metal by plastic deformation. This is typically achieved by squeezing, bending, drawing, or shearing the metal at a temperature below its recrystallization temperature. For example, the alloy can be hammered, stretched, and otherwise formed. This cold working can increase the hardness, yield strength, and/or tensile strength of the article formed from the alloy.

Spinodal aging/decomposition is a mechanism by which multiple components can separate into distinct regions or microstructures with different chemical compositions and physical properties. In particular, crystals with bulk composition in the central region of a phase diagram undergo exsolution. Spinodal decomposition at the surfaces of the alloys of the present disclosure results in surface hardening.

The heat-treated spinodal structure retains the same geometry as the original and the articles do not distort during heat treatment as a result of the similar size of the atoms.

The copper-nickel-tin alloy may be a spinodal alloy. Spinodal alloys, in most cases, exhibit an anomaly in their phase diagram called a miscibility gap. Within the relatively narrow temperature range of the miscibility gap, atomic ordering takes place within the existing crystal lattice structure. The resulting two-phase structure is stable at temperatures significantly below the gap.

Copper-nickel-tin spinodal alloys exhibit a beneficial combination of properties such as high strength, excellent tribological characteristics, and high corrosion resistance in seawater and acid environments. An increase in the yield strength of the base metal may result from spinodal decomposition in the copper-nickel-tin alloys.

Copper alloys have very high electrical and thermal conductivity compared to conventional high-performance ferrous, nickel, and titanium alloys. Conventional copper alloys are seldom used in demanding applications that require a high degree of hardness. However, copper-nickel-tin spinodal alloys combine high hardness and conductivity in both hardened cast and wrought conditions.

An inert atmosphere (e.g., including argon and/or carbondioixide/monoxide) and/or the use of protective covers (e.g., vermiculite, alumina, and/or graphite) may be utilized to maintain neutral or reducing conditions to protect oxidizable elements.

Reactive metals such as magnesium, calcium, beryllium, and/or tungsten may be added after initial meltdown to ensure low concentrations of dissolved oxygen.

Casting may be performed following melt temperature stabilization with appropriate superheat into continuous cast billets, parts, or shot.

Optionally, solution annealing 130 is carried out for from about 1 to about 12 hours at a temperature of from about 1350 to about 1625° F.

Cold working 140 refers to mechanically deforming a metal at a temperature below the recrystallization temperature. The metal becomes more difficult to deform as the amount of deformation increases. In other words, the material is work hardened or strain hardened. This step is optional.

Optionally, the metal may be further strengthened by heat treating 150. In some embodiments, the heat treating includes reheating in a temperature range of from about 600 to about 950° F. for from about 1 to about 8 hours to effect hardening.

The nickel may be present in an amount of from about 5 to about 25 wt %, including from about 10 to about 20 wt % and about 15 wt %. In more specific embodiments, the nickel is present in amounts of about 8 wt % to about 16 wt %, about 14 wt % to about 16 wt %, about 8 wt % to about 10 wt %, or about 10 wt % to about 12 wt %.

The tin may be present in an amount of from about 5 to about 10 wt %, including from about 6 to about 9 wt % and from about 7 to about 8 wt %. In more specific embodiments, the tin is present in amounts of about 5 wt % to about 9 wt %, or about 7 wt % to about 9 wt %, or about 5 wt % to about 7 wt %.

The manganese may be added in an amount of at least about 0.2 wt %, including at least about 0.5 wt %, at least about 1 wt %, and at least about 1.5 wt %. In more specific embodiments, the manganese is present in amounts of at least 4 wt %, at least 5 wt %, about 4 wt % to about 12 wt %, about 5 wt % to about 21 wt %, about 16 wt % to about 21 wt %, or about 19 wt % to about 21 wt %. In some embodiments, the maximum amount of manganese is at most 10 wt %, including at most 5 wt %, at most 3 wt %, at most 2 wt %, at most 1.9 wt %, at most 1.8 wt %, at most 1.7 wt %, at most 1.6 wt %, and at most 1.5 wt %.

In some specific embodiments, the copper-nickel-tin-manganese alloy contains from about 7 wt % to about 9 wt % nickel and about 5 wt % to about 7 wt % tin. These embodiments will also contain about 0.2 wt % to about 21 wt % manganese, and balance copper. It is specifically contemplated that these embodiments might contain about 5 wt % to about 21 wt %, about 16 wt % to about 21 wt %, or about 19 wt % to about 21 wt %, and balance copper.

In other specific embodiments, the copper-nickel-tin-manganese alloy contains from about 14 wt % to about 16 wt % nickel and about 7 wt % to about 9 wt % tin. These embodiments will also contain about 0.21 wt % to about 21 wt % manganese, and balance copper. It is specifically contemplated that these embodiments might contain about 5 wt % to about 21 wt %, about 16 wt % to about 21 wt %, or about 19 wt % to about 21 wt %, and balance copper.

The alloy may further include one or more other metals such as beryllium, chromium, silicon, molybdenum, iron, and zinc.

In some embodiments, the copper alloy contains from about 1 to about 5 wt % beryllium.

The copper alloy may contain from about 0.7 to about 6 wt % cobalt.

In specific embodiments, the alloy includes about 2 wt % beryllium and about 0.3 wt % cobalt.

In other embodiments, the alloy can contain beryllium in an amount of from about 5 to about 7 wt %.

The chromium may be present in an amount of less than about 5 wt % of the alloy, including from about 0.5 wt % to about 2.0 wt % and from about 0.6 wt % to about 1.2 wt %.

The article may be in the shape of a strip, a rod, a bar, a tube, or a plate.

In some embodiments, the article is a bushing, an instrument housing, a connector, a centralizer, a fastener, a drill collar, a mold for plastic shapes, a welding arm, an electrode, a cast component, or a certified ingot. The article may be an aircraft landing system or a component thereof.

It will be appreciated that variants of the above-disclosed and other features and functions, or alternatives thereof, may be combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims. 

1. An alloy comprising copper, nickel, tin, and from about 1.9 wt % to about 21 wt % manganese.
 2. The alloy of claim 1, wherein the nickel is present in an amount of from about 5 wt % to about 25 wt %.
 3. The alloy of claim 1, wherein the tin is present in an amount of from about 5 wt % to about 10 wt %.
 4. The alloy of claim 1, wherein the manganese is present in an amount of from about 1.9 wt % to about 10 wt %.
 5. The alloy of claim 1, wherein the manganese is present in an amount of from about 1.9 wt % to about 5 wt %.
 6. The alloy of claim 1, wherein the manganese is present in an amount of from about 1.9 wt % to about 2 wt %.
 7. The alloy of claim 1, wherein the manganese is present in an amount of from about 2 wt % to about 10 wt %.
 8. An article comprising a copper-nickel-tin-manganese alloy, wherein the manganese is present in in the alloy in an amount of from about 1.9 wt % to about 21 wt %.
 9. The article of claim 8, wherein the article is selected from the group consisting of a bushing, an instrument housing, a connector, a centralizer, a fastener, a drill collar, a mold for plastic shapes, a welding arm, an electrode, a cast component, and a certified ingot.
 10. The article of claim 8, wherein the article is a strip, a rod, a bar, a tube, or a plate.
 11. The article of claim 8, wherein the alloy comprises from about 5 wt % to about 25 wt % nickel and from about 5 wt % to about 10 wt % tin.
 12. The article of claim 8, wherein the article has at least one dimension in excess of about 5 inches.
 13. A method for producing an article, comprising casting a copper-nickel-tin alloy that also contains 0.2 wt % to 21 wt % manganese to produce the article.
 14. The method of claim 13, further comprising cold working the article.
 15. The method of claim 13, further comprising precipitation hardening the article by heat treatment with or without cold working.
 16. The method of claim 13, wherein the nickel is present in an amount of from about 5 wt % to about 25 wt % of the article; and wherein the tin is present in an amount of from about 5 wt % to about 10 wt % of the article.
 17. The method of claim 13, wherein the manganese is present in an amount of from about 0.2 wt % to about 10 wt % of the article.
 18. The method of claim 13, wherein the manganese is present in an amount of from about 0.2 wt % to about 5 wt % of the article.
 19. The method of claim 13, wherein the manganese is present in an amount of from about 0.2 wt % to about 2 wt % of the article.
 20. The method of claim 13, wherein the manganese is present in an amount of from about 0.2 wt % to about 1.9 wt % of the article. 